I am using RHEL 6 Desktop for last 6 months..
Following are the essential softwares required/installed on my machine to ensure my productivity:
1. Mail: Lotus Notes 9
2. Office Suite: IBM Lotus Symphony 3.1, Open Office 3.4.1
3. PDF Docs: Foxit Reader, Adobe Reader
4. Screenshots: Shutter
5. Notes, Customer Activity Tracking: GNote
6. Web Browser: Firefox, Chrome
7. Virtualization: VMWare Workstation, VMWare Player (Virtual Image: Domino Server, Domino Designer, Domino Administrator)
8. Backup to External Hard-drive: GrSync
9. Media Player: VLC Media Player
10. Remote Control: Teamviewer, Tiger VNC Viewer
11. Graphics: GIMP, Pencil
This list covers all the installations/additions I have done to Vanilla RHEL desktop... Apart from Domino Designer, there is nothing for which I need a Windows environment.. I wish if we can have a Linux version of Domino Designer as well some day !!